Nowadays mobile equipment systems generally use special smart card applications. These are used to divide the MS (Mobile Station) into a so-called general ME (Mobile Equipment) part functioning in a mobile equipment system of a defined type and into a separate network/subscriber-specific part, which is also known more generally as a so-called SIM (Subscriber Identity Module) facility.
A subscriber connection is usually needed these days for communicating with terminal equipment in an established data communication network. The connection is used to identify, among other things, one or more data transmission networks, wherein communication is permissible, and detailed settings related to the subscriber connection, such as, for example, network/operator-specific data (encryption algorithms, among other things) and subscriber-specific data, such as, for example, the IMSI (International Mobile Subscriber Identity).
According to the known technology, data is stored on a small physically implemented silicon chip connected with the terminal equipment. At least storing means are arranged on the chip for storing the above-mentioned data and for using it in the terminal equipment as well as a possible micro controller functioning as the processor unit. In some environments the processor functionality may also be arranged in the terminal equipment module proper. However, as a general rule, the SIM facility is usually arranged on a plastic base as a compact and physical entity, which may also be called a SIM card.
For SIM cards of the known kind there is a standard connection in the mobile terminal equipment including connecting pins for connecting it electrically to the terminal equipment. The overall structure of the SIM card includes, besides the possible micro controller arranged on it, also various storing means and auxiliary circuits relating for example to the management of its internal data transmission and operating voltage.
The micro controller possibly placed on the SIM card is used to carry out the SIM application, which has several different manufacturers, as is known. In the state of the art, network operators or other such providers of subscriber connection services give these manufacturers their own instructions and settings, and the SIM applications will be in accordance with these in the end. The application includes, among other things, the micro controller's instruction set and file references for reading, interpreting and updating the network, terminal equipment and subscriber data arranged in the storing devices, as well as execution of authentication and encryption algorithms.
Solutions have been sought for quite a long time in the mobile station branch to replace the fixed SIM facility, for example, in M2M equipment. Almost without exception, state-of-the-art SIM smart cards cause problems and strains for all parties acting with the terminal equipment. Firstly, the distribution logistics required by the supplying of SIM cards and generally their arrangement in terminal equipment is problematic to terminal equipment manufacturers and device dealers.
Another drawback for terminal equipment manufacturers are the significant cost items caused by SIM cards as well as design and structural limitations and size limitations in general, which they establish for terminal equipment and equipment modules. Even the arranging of standard connections required by the state-of-the-art SIM card in the terminal equipment constitutes a significant cost item in serial production of terminal equipment.
Another drawback especially affecting the subscriber using the terminal equipment is the risk of destruction of data stored in SIM cards of the known kind, for example, in situations where the supply of power to the terminal equipment is interrupted for some reason in the middle of the communication carried on with it.
Known technology relating to the SIM facility is described in the FI-104139B (Nokia Networks Oy), FI-104937 (Sonera Oyj), WO-98/53629 (Motorola, Inc), EP-1037159A2 (Nokia Mobile Phones LTD.) publications. Of these, the FI-104937 publication (Sonera Oyj) presents a method for carrying out a smart card facility, which allows implementation of comprehensive services with the data communication device. However, this provides no solution to the drawbacks mentioned above.
Besides these, the state of the art also knows solutions for reconfiguration of the SIM facility through the data transmission network. Examples of such are presented, for example, in the EP-0 562 890 B1, U.S. Pat. No. 6,097,967, WO 00/40048 and FI-108390 publications. Such reconfigurations may include, for example, activation of mobile station services or downloading of so-called value-added services in the terminal equipment. However, to carry out these measures the terminal equipment must be in such a state that the actual SIM facility is already arranged in the terminal equipment, and in connection with it additional data is just downloaded from the data transmission network.
Such measures, for example, are also known, which are taken in connection with a change of the subscriber connection in order to transfer subscriber-specific data, such as, for example, SMS (Short Data Message) messages and telephone memo data from the old SIM card to the new card. This step may be performed either at the terminal equipment or, for example, at the network operator's service outlet with a special configuration application.